Why are the python style modules of freestyle not working?
Yes there have been changes made to the freestyle api in various versions since it was added to blender. Freestyle is still there and working, it is just that some of the older python scripts might need updating. I'm not sure of any list of these changes, but you could compare the above page to this first release of the freestyle api. You could find the api used in other releases by starting here.

The first link you have are examples from five years before freestyle was added to blender and may not be close to the python support that was included with the first version of freestyle in blender.

Looking at the console output when using any of these older scripts might be helpful in finding where they fail.

The link to dfelinto's github repo has the same files that are included with blender releases, these files in his repo are identical to the current official development version of blender. Dalai is one of the blender developers and that repo is a copy of blenders code with some changes that he is working on.